We consulted and collaborated with researchers from NCI and other institutions on the design and statistical analysis of a broad range of laboratory studies, including: studies conducted in the Laboratory of Cellular Carcinogenesis and Tumor Promotion establishing that dietary retinoic acid inhibits the formation of carcinogen-induced skin tumors in mice and demonstrating differences among transgenic mouse strains in liver concentrations of retinyl palmitate; studies carried out in the Laboratory of Cellular and Molecular Biology demonstrating an increased frequency of chromosome aberrations after exposure to fluorescent light in cultured cells from hereditary retinoblastoma patients and in mutant Chinese hamster ovary cell lines with known DNA-repair defects; studies performed by researchers in the Laboratory of Molecular Carcinogenesis showing that the frequency of UV-induced mutations increases as individuals age, mirroring a decrease with age in their inherent ability to repair UV-induced DNA-damage; investigations into whether a base alteration at a specific nucleotide in a DNA sequence can change the frequency of UV-induced mutations at nucleotides some distance from the original altered nucleotide; a study in the Laboratory of Human Carcinogenesis showing that mutations in the p53 gene are much more likely to occur at nucleotide pairs that are strongly conserved in evolution; an investigation conducted in the Laboratory of Molecular Pharmacology examining the expression of various proteins in the p53 DNA-damage-induced pathway in human melanoma cell lines; a study in the Laboratory of Biological Chemistry demonstrating that 7-hydroxystaurosporine significantly alters the cell cycle of leukemic cell lines (e.g., Jurkat cells); a study by researchers in the Dermatology Branch showing that patients with Alzheimer's disease and Downs syndrome appear to be defective in the repair of some type of DNA damage induced by fluorescent light through the production of oxygen radicals; experiments performed in the Navy Medical Oncology Branch to examine the frequency of interlocus translocations involving immunoglobulin and T-cell antigen receptor genes in transgenic mice; a study at the Yale University Radiobiology Laboratory to compare the frequency and size of clones with a mutation in the p53 gene in sun-shielded and sun-exposed regions of normal human skin; and an investigation by the University of Minnesota Laboratory of Environmental Medicine and Pathology to determine if chromosomal translocations and inversions are more likely to occur in men exposed to pesticides